This invention relates to a D.C. brushless air fan and particularly a D.C. brushless air fan that offers has high quality, no dead points, and is oil leak-proof and no maintenance.
With rapid developments and innovations of electronic products, particularly in computer industry, heat generation and dissipation problem of electronic elements has become a critical and important issue. D.C. brushless air fans are widely used to attack this problem, especially personal computers (note book computers), cars, household appliances, audio products, and many popular and fashionable electronic products such as VCD, DVD, etc.
D. C. brushless air fans are especially suitable for electronic products because of their simple structure, small size and using convenience. However there are still problems and deficiencies unresolved. For instance, the production processes of D. C. brushless air fans are still too complicated and result in higher costs of production. Lubrication oil contained in the spindle tends to spin away under high speed rotation and may result in not enough lubrication oil after operating a period of time, and will generate excessive heat in the allowance between the spindle and bearing, and become not operating properly. Moreover, there are dead points in the air fans that could cause the air fans not be able to start initially. Whenever these problems happen, it needs professional technicians to do maintenance. It hinders users"" operations, and causes a lot of losses in human and material resources. There are still rooms for improvements.
The primary object of the invention is to resolve the foregoing disadvantages. The invention comprises a rotor, a stator and a casing. The rotor includes a spindle coupled with vanes, and a magnetic bushing and adhesive magnet located in the vanes. The stator includes a ferrite core housed an oil-retained bearing, an upper and a lower insulation plate located respectively at an upper and a lower end of the ferrite core. The lower insulation plate includes a hollow and a solid snap ring and a circuit board. The casing has a center strut with a cavity formed therein. The spindle is coupled with an oil cap which has an annular oil trough to prevent oil from spinning out and leaking. The lower insulation plate has inverse hooks formed in diagonal fashion to engage with latch sections formed symmetrically about the axis of the center strut. The latch sections have axial grooves directing toward the bottom.
The foregoing, as well as additional objects, features and advantages of this invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.